Upper Limb Asymmetries of Movement Sense and Sense of Effort: The Contribution of Gender and Handedness.

Motor Control;Industrial and Operations Engineering;Engineering;Industrial & Operations Engineering

Scotland, SamanthaArmstrong, Thomas J. ;

University of Michigan

关键词: Motor Control;    Industrial and Operations Engineering;    Engineering;    Industrial & Operations Engineering;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/99857/sscotlan_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Asymmetry in upper limb performances may have multiple origins.The aim of this research is to determine the contribution of sensory and motor processes to asymmetries in movement sense and sense of effort when considering gender and handedness.The distinction between gender and handedness effects, while often ignored, may shed new light on human performances.The first study investigated asymmetry in movement sense using contralateral reproductions of vibration induced illusions of movements in right (RH) and left (LH) handed young adults of both genders. Females were found more sensitive to vibratory stimulations and less asymmetric than males in movement reproduction. The asymmetry observed in males was related to handedness. Both asymmetry and sensitivity were primarily sensory in origin. The second study investigated asymmetries in the sense of effort and targeted the motor component. Both RH and LH adults were divided into three groups based on hand strength differences.A 20% MVC reference grip force was matched with the same or opposite hand (of the reference). The matching error increased with hand strength differences for RH only, suggesting that the sense of effort is a consequence of both muscle strength differences and an intrinsic asymmetry of the motor component that may vary with handedness. The last study investigated the relative contributions of efferent copy and sensory feedback to the sense of effort. Vibration was used to distort the sensory information from muscles providing the reference in the grip matching task. Visual feedback of the reference hand was also manipulated. The hand/hemisphere systems were found to differ significantly in their dependence on proprioceptive information during force reproduction, with the left hand being more feedback dependent.These findings lead us to suggest that hand preference and gender contribute to differences in movement representation, force production and sense of effort that may result from the combination of cortical structural differences and information processing specific to each hemisphere, gender and handedness group.